Improvement in hollow augers



M. L. EDWARDS.

Hollow Augers. A

r Patented De'c.3,1872.

1tive position to the center as the others.

PATENT CFFIGE.

MARTIN L. EDWARDS, OF SALEM, OHIO.

IMPROVEMENT IN HOLLOW AUGERS.

Specification forming part of Letters Patent No. 133,573, dated December3, 1,872.

To all whom 'it may concern:

Be it known that I, MARTIN L. EDwARDs, of Salem, in the county ofColumbiana and State 'of Ohio, have invented new and useful Improvementsin'Hollow Angers for Cutting Tenons, of which the following is aspecification:

My invention has for its object the cuttin of tenons of differentdiameters on wood by a tool, the knives of which are adjustableconcentrically to cut a larger or smaller tenon; and my said inventionconsists in the construction, arrangement, and combination of theseveral parts of the said tool, as hereinafter more fully described.

In the accompanying drawing, Figure l represents a front elevation orface view of my improved hollow auger for cutting tenons, Fig. 2represents a longitudinal section of the same, the line of sectionpassing through the cutters in the headflange; Fig. 3 represents a viewof the rear side of the head-flange, the plate for adjusting the knivesand guides being removed; Fig. 4 represents an inside face view of theplate which adjusts the knives and guides; and Fig. 5, a side and endview of one of the cutters.

The hollow auger for cutting tenons consists of a hollow shank, a,provided with an internal screw-thread, and at one end with a headconsisting of a liange, l), which flange is provided with 'fourequidistant slots, c, extending from the central opening of the shank ato the periphery of the iiange b. These slots are not exactlyradial-that is to say, each two opposite slots are not in the samediametrical linetheir inner ends not being exactly opposite each other;but each slot has the same rela- In these slots c the longitudinaltongues d, formed on the inner side of sliding blocks e, have a freemovement toward and from the center, being prevented from moving out ofthe slots c by means of short platesf extending from the outer end ofthe tongues d inwardly to about half their lengths, and which bearagainst the rear side of the head-flange b. On the outside ofthe pl atesf tongues g are formed, which have concentric grooves or ways h cutacross them to receive corresponding concentric ribs i formed on theinner surface of an adjustingplate, j. This plate j is provided with acenvfirmly in place.

tral opening to admit of its being passed over the shank a, on which itmay be moved at pleasure. The ribs t' on its inner surface areeccentrically curved or inclined, and each one bears the same relativeposition to its corresponding groove It on the tongue g, and to thecenter of the hollow shank a, so that if the plate j is turned one wayor the other its ribs fi, operating the blocks c through the grooves hintheir tongues g, will force the sliding blocks e either toward or fromthe center in their slots c to perfectly equal distances, and the innerends of the blocks will therefore be always concentric and equidistantin whatever position they may have been placed by the plate j. This adjusting-plate j is held to the flange b, and in any desired positionrelatively to the distance of the sliding blocks@ from the center bymeans of set-screws k, which pass through curved concentric slots l,formed at opposite sides in the plate j, and which set-screws pass intoscrewholes formed in the ange b, shoulders m formed on them near theirouter ends bearing against the outer face of the plate j and holding itsliding blocks c are cut out to conform to the periphery of the centralopening of the shank a, and two of them on opposite sides have slots ncut in the surface of their outer ends, in which slots the square4shanks o of the cutting knives p fit snugly, screws r passing throughsaid shanks into the sliding blocks, rigidly securing the knives intheir respective blocks e. A portion of the sliding blocks e under theknives p is cut away to leave a space for the free passage of chips,which thereby will be. prevented from clogging the knives. Into thehollow shank a, from its near end, screws the screw-head s of themandrel t, which mandrel is provided with a square end, a, by means ofwhich it may be attached to a lathe or other machine for revolving thetool. this mandrel the length of the tenon is determined; for when itis'secured into the shank a to such a distance that the distance fromthe surface of its screw-head s to the edge of the knives p is equal tothe desired length of the tenen to be cnt, the mandrel is kept in suchposition by means of a shouldered sleeve, fv, which has a free movementon the smooth, round shank of the mandrel, and which is then moved onsaid shank until its shoulder firmly The inner ends of the four By meansof bears against the end of the hollow shank a, and secured by eset-screw, w. When the end of the tenon which is being out reaches thesurfe-ce of the said screw-head s of the mendrel the tool can out nofurther, and thus the length of the tenon can be determined andregulated by the mandrel t.

My improved tenen-cutter can be made of` size of tenon by means of theplate j, which is released or held in position merely by the setsorewsk, thus rendering the tool simple, and easily handled and adjusted.

Having described my invention, I claim- The hollow auger for cuttingtenons, all its parts being arranged and constructed as described.

MARTIN L. EDWARDS. Witnesses:

B. S. AMBLER, PETER AMBLER.

